Debris collecting screen for electroplating tanks



Feb. 20, 1968 J. L. WILLIAMS DEBRIS COLLECTING SCREEN FOR ELECTROPLATINGTANKS Filed June 50, 1965 .8 mm M W L m F E J Fig. 3.

United States Patent This invention relates generally to devices forcollecting and removing debris from electroplating tanks and moreparticularly to a screen structure which may be placed in the bottom ofsuch tanks for collecting debris and removed for cleaning the tank.

In conventional electroplating tanks it frequently happens that partswhich are being plated, pieces of anode material or other miscellaneousobjects, fall to the bottom of the tank. This often causes metalliccontamination of the plating solution, and the only conventional methodof removing such objects from the tanks is to drain the platingsolution. This causes expensive delays while the plating apparatus isout of service. Unless the tanks are drained, the only other method ofremoving debris is by the use of rakes, magnets, hooks and the like, andsuch procedure can cause damage to the tank bottoms and the airagitation equipment located in the bottom of the tanks. Furthermore,there is no conventional apparatus provided for preventing damage to thetank bottoms and the air agitation equipment when anode spears or otherheavy objects drop to the bottom of the tank.

Accordingly, the principal object of this invention is to provide acollecting means which may be placed in relatively close proximity tothe bottom of an electroplating tank for collecting any objects whichmay drop within the tank, the collecting means being readily removablefrom the tank for removing such objects.

A further object of this invention is to provide a screen structurewhich may be hung from the top of an electroplating tank and located inrelatively close proximity to the bottom of the tank for collecting andremoving debris.

In accordance with the invention there is provided a debris collectingscreen for electroplating tanks comprising a piece of open mesh clothformed of material which is not decomposable by an electroplatingsolution, the sides of said piece of cloth being reinforced by metallicrods, the ends of said piece of cloth being reinforced by flexiblestrips, and suspension means attached to the sides of said cloth forsuspending the screen in close proximity to the bottom of anelectroplating tank.

The full nature of the invention will be understood from theaccompanying drawings and the following description and the claims.

FIG. 1 is a top plan view of the debris collecting screen as provided inaccordance with this invention.

FIG. 2 is an end view of the screen illustrated in FIG. 1.

FIG. 3 is a transverse cross section of an electroplating tankillustrating the screen of FIG. 1 suspended in said tank.

Referring to the drawings, there is provided a debris collecting screenconsisting of a piece of cloth 10 formed of a material such, forexample, as nylon, which is impervious to and is not attacked byelectroplating solutions. The cloth is of relatively open mesh so thatfluid will drain through it readily as the structure is removed from anelectroplating tank. The sides of the cloth member are reinforced bysteel rods 11 which may be coated with any material such, for example,as what is commonly called plastisol, having such characteristics thatit will prevent any chemical reaction between the steel rod and theelectroplating solution. The rods may be attached "ice to the cloth inany suitable manner such, for example, as by folding the edge of thecloth over the rods and sewing the folded-over portion to the main bodyof the screen. The central portion of the cloth member may also bereinforced by similarly coated steel rod 12 and attached to the screenby a cloth panel sewn or stitched to the screen structure.

The ends of the screen may be reinforced by a flexible member 14 formedof material such, for example, as polyethylene, or any other materialwhich is impervious to electroplating solutions and which has sufficientstiffness to flatten the screen when it is suspended in anelectroplating tank and sufficient resilienceto bend when the screen islifted from the tank. Members 14 may, for example, be approximately 7thick and in width and may be attached to the screen by means of thepocket forming members 15 formed of nylon cloth and sewn to the screen.

For suspending the screen in an electroplating tank there are provided aplurality of cords 16 formed of polyethylene material and attached tothe screen by tying or otherwise fixing one end to the reinforced sidesof the screen. The other end of each cord may be provided with a hook 17formed of steel and coated with plastisol.

As illustrated in FIG. 3, conventional electroplating apparatus includesa tank 20 having anodes 21 suspended on hooks 22 from anode rods 23. Theobjects to be electroplated may be suspended from a cathode rod 24 andhung in the electroplated solution as illustrated at 25. At the bottomof the tank there are provided air emitting devices 26 for agitating theelectroplating solution.

The debris collecting screen of this invention may be suspended withinthe tank 21 by placing the hooks 17 on the anode rods so that the screenassumes the position illustrated in FIG. 3 wherein the screen is spacedupwardly from the bottom of the tank and over the air agitatingapparatus.

As previously mentioned, the reinforcing members 14 are suflicientlystiff to cause the screen to assume a flat position when suspended inthe tank. Any debris which drops into the tank will be caught by thescreen and the screen may then be periodically removed in order toremove collected debris. During removal the members 14 will bendupwardly to prevent collected material from dropping off the screen. I

From the foregoing description it will be apparent that this inventionprovides means for collecting debris in electroplating tanks whicheliminates damage to the tanks which might result from removing suchdebris by the use of rakes, magnets, hooks, and the like. Debris may beremoved at any time in order to prevent any metallic contamination ofthe plating solution, and it is not necessary to drain the platingsolution from the tanks. Thus, the plating apparatus will not be out ofservice for any material length of time and expensive delays areeliminated.

The invention claimed is:

1. In an electroplating cell, a debris collecting screen comprising afabric member having a fluid pervious mesh and a configurationcorresponding to the bottom of a tank, stiff reinforcing rods fixed tothe longitudinal edges of said member and extending substantially theentire length thereof, flexible reinforcing members fixed to ends ofsaid member and extending substantially the full width of said fabricmember, and means attached to said rods for suspending said fabricmember adjacent the bottom of said tank, said flexible members havingsufficient stiffness to maintain said fabric member parallel to saidtank bottom.

2. A debris collecting screen according to claim 1 wherein said fabricmember comprises a material which i immune from attack by anelectroplating solution.

3. A debris collecting screen according to claim 1 wherein said rodscomprise metal coated with a material which is immune from attack by anelectroplating solution.

4. A debris collecting screen according to claim 1 wherein saidsuspending means comprises a plurality of flexible members attached tosaid rods intermediate the ends thereof and hooks attached to saidflexible members.

5. A debris collecting screen according to claim 1 wherein said flexiblereinforcing members comprise a plastic material immune to attack by anelectroplating solution.

6. A debris collecting screen according to claim 1 wherein said fabricmember includes at its corners pocket members for receiving the ends ofsaid flexible members. 15

5 wherein said fabric member includes portions folded over said rods andstitched to said member.

References Cited UNITED STATES PATENTS 10/1950 Cates 210-237 HOWARD S.WILLIAMS, Primary Examiner.

D. R. JORDAN, Assistant Examiner.

1. IN AN ELECTROPLATING CELL, A DEBRIS COLLECTING SCREEN COMPRISING AFABRIC MEMBER HAVING A FLUID PREVIOUS MESH AND A CONFIGURATIONCORRESPONDING TO THE BOTTOM OF A TANK, STIFF REINFORCING RODS FIXED TOTHE LONGITUDINAL EDGES OF SAID MEMBER AND EXTENDING SUBSTANTIALLY THEENTIRE LENGTH THEREOF, FLEXIBLE REINFORCING MEMBERS FIXED TO ENDS OFSAID MEMBER AND EXTENDING SUBSTANTIALLY THE FULL WIDTH OF SAID FABRICMEMBER, AND MEANS ATTACHED TO SAID RODS FOR SUSPENDING SAID FABRICMEMBER ADJACENT THE BOTTOM OF SAID TANK, SAID FLEXIBLE MEMBERS HAVINGSUFFICIENT STIFFNESS TO MAINTAIN SAID FABRIC MEMBER PARALLEL TO SAIDTANK BOTTOM.